Climate Regime Shifts in Marine Ecosystems

Marine ecosystems are subject to abrupt and persistent reorganisations, known as climate regime shifts, that arise when external climatic forcing exceeds ecological thresholds. These shifts manifest as widespread changes in physical conditions such as sea surface temperature and wind patterns, and as biological responses including alterations in community composition, trophic structure and biogeographical distributions. Drivers range from large-scale oscillations—such as the El Niño–Southern Oscillation or shifts in major ocean gyres—to anthropogenic warming in combination with natural variability. Notable events include the global transition in the mid-1980s that triggered synchronous changes from polar waters to the equator, and regional rearrangements observed in currents like the Humboldt Current and the North Pacific. Consequences extend to fisheries yield, biodiversity loss, habitat degradation and socio-economic impacts on coastal communities. Understanding the mechanisms, predictability and resilience of these shifts is crucial for anticipating future alternations under ongoing climate change and for implementing adaptive management strategies.

Research from Nature Portfolio

Long-term monitoring of Copper Rockfish has revealed that these fish enter extended winter sheltering within complex shoreline boulder habitats, a behaviour modulated by strong La Niña winters and intense Arctic outflow windstorms. The duration of sheltering, often exceeding six months, appears to confer energetic advantages and may reflect an adaptive response to variable winter conditions, with implications for population dynamics and habitat management under changing climatic regimes.

Climate Regime Shifts in Marine Ecosystems publication trend

The graph below shows the total number of articles in climate regime shifts in marine ecosystems across all publications each year (not limited to Nature Index journals).

Technical terms

Regime shift: A large, abrupt and persistent change in the structure and function of an ecosystem driven by climatic or environmental forcing.

El Niño–Southern Oscillation (ENSO): A coupled ocean–atmosphere phenomenon in the tropical Pacific characterised by alternating warm (El Niño) and cool (La Niña) phases that influence global climate patterns.

Principal component analysis (PCA): A statistical technique that reduces the dimensionality of data sets by identifying orthogonal axes (components) that explain the greatest variance.

Change-point analysis: A method for detecting moments in time series when the statistical properties, such as mean or variance, undergo significant shifts.

References

1. Global impacts of the 1980s regime shift. Global Change Biology (2015).
2. Climate and weather factors affecting winter sheltering by shoreline Copper Rockfish Sebastes caurinus in Howe Sound, British Columbia. Scientific Reports (2020).
3. Climate Variability Patterns and Their Ecological Effects on Ecosystems in the Northwestern North Pacific. Frontiers in Marine Science (2020).
4. Climate Variability Impacts on the Fishery Ecosystem Structure in the Humboldt Current System. Ecosystem Health and Sustainability (2024).